General Thoughts: Mathematics (1 Viewer)

Mudkip94

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wat did every get for that tile one the last one how does it equal 1980 and something about 10 percent extra for breakage my equation was...

178.2 x 0.09 = 1980 ....i was so glad that i got it rite 2 marks in the bag

the area of the rectangle is 162 +10%[16.2]=178.2 and the tile is 0.09^2

so ye i just did 178.2 x 0.08 = 1980 soo happpy
Umm... 178.2 x 0.09 ≠ 1980

I done:

162 x 1.1 = 178.2
178.2 / 0.09 = 1980
 

silence--

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For that last question i dont think you were allowed to put in elipses, that would be too easy. I think they were looking for an actual formula. I might have got it if i had another few minutes to work some stuff out.
what's wrong with ellipses

it asked you to find a general statement for the nth cube, not a formula.

maybe it is "too easy", but remember this is sc maths.
 

brent012

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what's wrong with ellipses

it asked you to find a general statement for the nth cube, not a formula.

maybe it is "too easy", but remember this is sc maths.
Ok looked it up on wikipedia and i think this is what we were looking for. Thats the real answer there, but maybe they will accept other answers. (eg elipse one)

 

silence--

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oh

ohh

that's pretty cool

but too much for sc i think haha
 

silence--

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no.

take 1^3 + 2^3 = 9

(1+2)^2 = 9

honestly mad props to everyone who got that in the exam.

ellipses would still be a valid answer i reckon, too advanced for sc :/
 

Hayzazz

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Oh I get it. I was just looking at the n and I thought that it was supposed to turn into an n^3, not an n^2. o__O
 

brent012

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Im not sure, just took it off wikipedia to show everybody. It seems to work aswell.

I also agree that its far too difficult for SC, just like proving my point xD.
 

chevlr

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Im not sure, just took it off wikipedia to show everybody. It seems to work aswell.

I also agree that its far too difficult for SC, just like proving my point xD.
yeh i think its called mathematical induction, and its taught in 3u maths in yr 12, so they wouldnt want you to do that.
 

jniranjan

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i finished one of the section 2 part b q's in about 15 secs. that was the one where you just had to put the resons in and fill out some of the missing angles.

Also, with that birthcake question, neither abc or d fitted the answer for me. I did 2(pie x 10^2) - 2(pi x 3^2) (the diameter was 20,and 6 for the hole)

And one of the questions, 2 of the answers was 18 and -18. which one was correct.

Did anyone here get the question with the equilateral triandge and the cube. AHHHH! That pissed me off.
 

brent012

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i finished one of the section 2 part b q's in about 15 secs. that was the one where you just had to put the resons in and fill out some of the missing angles.

Also, with that birthcake question, neither abc or d fitted the answer for me. I did 2(pie x 10^2) - 2(pi x 3^2) (the diameter was 20,and 6 for the hole)

And one of the questions, 2 of the answers was 18 and -18. which one was correct.

Did anyone here get the question with the equilateral triandge and the cube. AHHHH! That pissed me off.
Somebody posted a diagram in the first few pages, the answer was 45 according to their diagram.
 

chevlr

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i finished one of the section 2 part b q's in about 15 secs. that was the one where you just had to put the resons in and fill out some of the missing angles.

Also, with that birthcake question, neither abc or d fitted the answer for me. I did 2(pie x 10^2) - 2(pi x 3^2) (the diameter was 20,and 6 for the hole)

And one of the questions, 2 of the answers was 18 and -18. which one was correct.

Did anyone here get the question with the equilateral triandge and the cube. AHHHH! That pissed me off.
yeh, i only got that the 2nd time i looked at it when i realised the sides of the square and the triangle were of equal length, so then it all just worked
 

msaint

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wat did every get for that tile one the last one how does it equal 1980 and something about 10 percent extra for breakage my equation was...

178.2 x 0.09 = 1980 ....i was so glad that i got it rite 2 marks in the bag

the area of the rectangle is 162 +10%[16.2]=178.2 and the tile is 0.09^2

so ye i just did 178.2 x 0.08 = 1980 soo happpy
i worked it out by
900 cm = 9m
so 30 tiles of 30cm fit along the width

1800cm =18m
so 60 tiles fit in the length

60x30=1800

10% of 1800 = 180
1800 + 180 = 1980
 

maryjill

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I'm pretty proud
my tutor said he doesn't expect much from me
hahaha
so If I just passed hes happy
But non-calculator was a breeze cause I had been studying for like 2 weeks without a calculator for it
I even found myself not using my calculator in section 2 and I was like why am I doing it the hard way after like 3 questions
hahahah
durrrr:D
 

BobMoo

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Fairly easy test apart from 2nd last question in non-calculator and last question in calculator. Damn I guessed the second last question i put 40 but was going to put 45 but said stuff it. and now I realise its 45. For the last question I put n^3+(n-1)^3+(n-2)^3...+(n-n)^3. dunno if dats rite :S
 

BobMoo

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i finished one of the section 2 part b q's in about 15 secs. that was the one where you just had to put the resons in and fill out some of the missing angles.

Also, with that birthcake question, neither abc or d fitted the answer for me. I did 2(pie x 10^2) - 2(pi x 3^2) (the diameter was 20,and 6 for the hole)

And one of the questions, 2 of the answers was 18 and -18. which one was correct.

Did anyone here get the question with the equilateral triandge and the cube. AHHHH! That pissed me off.
For that cake quetion, it turns out to be b i think cos you have to work it out in terms of pi, so for now you just leave it out and put it in the end. It turns out to be 2((10^2)-(3^2))pi, which turns out to be 182pi which was b.

I think for that 18 and -18 it was 18 thats wat i got.

Those other 2 qestions were really hard i shuldve just skipped em and checked my other answers =/
 

firstneg

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ah i think that the second last one was 1^3,2^3 ect because it was three demential not two,,,,
but ah i dont know
i will be lucky to get a band four.
 

AV_knights

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For the last question i got C=n^3+x^2 where x was the sum of all the previous side lengths
 

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